This invention relates to ethanolamine derivatives and acid addition salts thereof. More specifically, this invention relates to 1-(3,4-methylenedioxyphenyl)-2-alkylaminoethanol compounds and to methods for preparing same. The ethanolamine derivatives and their salts show strong pharmacological activity, especially .beta.-adrenergic receptor blocking activity. The compounds are, therefore, expected to be useful in the treatment or prevention of nervous disorders such as heart disease, hypertension, myocardites and pheochromocytoma.
The compounds which are the subject of the present invention are 1-(3,4-methylenedioxyphenyl)-2-alkylaminoethanol compounds and are represented by the formula ##STR1## wherein R represents a straight or branched chain alkyl group having 2 to 6 carbon atoms, such as an ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, n-amyl, isoamyl or n-hexyl group.
The 1-(3,4-methylenedioxyphenyl)-2-alkylaminoethanol compounds may be employed in the form of the free amine, or in the form of a salt. Suitable salts are the acid addition salts such as, for example, the salts of inorganic acids such as the hydrochloride, hydrobromide, phosphate and sulfate, the organic acid salts such as the oxalate, lactate, tartrate, naphthoate, acetate, salicylate, citrate, benzoate, adipate and maleate. The relatively insoluble salts such as 1,1'-methylene-bis-(2-hydroxy-3-naphthoate) are particularly useful since its physical properties enable it to remain in the blood at a constant level. Salts prepared from an acidic synthetic resin, such as the salts of a sulfonated polystyrene resin, may also be employed. The sulfonated polystyrene resin sold under the trademark ZEO-KARB 225 from The Permutit Co., Ltd., Great Britain is an example of a suitable synthetic resin.